VOA标准英语2015--科学家寻找更好的途径解决鲨鱼面临的威胁

Scientists Seek Better Understanding of Threats Faced by Sharks 科学家寻找更好的途径解决鲨鱼面临的威胁

COCONUT¹ ISLAND, HAWAII—

With many shark species endangered or threatened as a result of pollution and other problems, scientists are getting a shark’s-eye view of their environment to better understand the dangers they face.

A University of Hawaii research site on Coconut Island, minutes by motorboat from the shore of Oahu, is a good place to observe sharks, since they’re native to local waters. Some are kept in a sheltered bay for study.

Carl Meyer does research on "when sharks are feeding and hopefully how much they’re eating. That’s what we use these captive animals for.”

Scientists also monitor the behavior of sharks at sea, placing sensing pellets in their food to monitor digestion², measuring the animals and then releasing them with radio-equipped electronic tags attached to their fins³. The researchers study tiger sharks, sandbar sharks, blacktip sharks and others, and they recently fitted a sandbar shark with a camera for a rare shark’s-eye view of its daily activities.

“When we recovered the camera," Meyer said, "we saw that the shark had spent the day in a large aggregation⁴ of sharks, not just sandbar sharks but also blacktip sharks and many, many scalloped hammerhead sharks.”

Sharks are swift and lethal⁵, but don’t usually prey⁶ on humans. Meyer said the rare attacks are amplified⁷ by the media and dramatized in films like the 1975 thriller⁸ "Jaws⁹."

He said sharks are important top-level predators¹⁰ that help maintain the balance of the marine¹¹ systems. Those systems are threatened by pollution, climate change and commercial fishing, as fishermen target sharks for the Asian food market and kill them in the process of harvesting other species.

Meyer said humans are more of a risk to sharks than sharks are to humans.

"Never before in the natural history of the world have we seen a species become so dominant¹² and so able to alter the natural environment,” he said.

And the results of those environmental changes cannot always be predicted, he said.

1 coconut   

n.椰子

参考例句：

• The husk of this coconut is particularly strong.椰子的外壳很明显非常坚固。
• The falling coconut gave him a terrific bang on the head.那只掉下的椰子砰地击中他的脑袋。

2 digestion   

n.消化，吸收

参考例句：

• This kind of tea acts as an aid to digestion.这种茶可助消化。
• This food is easy of digestion.这食物容易消化。

3 fins   

[医]散热片；鱼鳍；飞边；鸭掌

参考例句：

• The level of TNF-α positively correlated with BMI,FPG,HbA1C,TG,FINS and IRI,but not with SBP and DBP. TNF-α水平与BMI、FPG、HbA1C、TG、FINS和IRI呈显著正相关，与SBP、DBP无相关。 来自互联网
• Fins are a feature specific to fish. 鱼鳍是鱼类特有的特征。 来自辞典例句

4 aggregation   

n.聚合，组合；凝聚

参考例句：

• A high polymer is a very large aggregation of units.一个高聚物是许多单元的非常大的组合。
• Moreover,aggregation influences the outcome of chemical disinfection of viruses.此外，聚集作用还会影响化学消毒的效果。

5 lethal   

adj.致死的；毁灭性的

参考例句：

• A hammer can be a lethal weapon.铁锤可以是致命的武器。
• She took a lethal amount of poison and died.她服了致命剂量的毒药死了。

6 prey   

n.被掠食者，牺牲者，掠食；v.捕食，掠夺，折磨

参考例句：

• Stronger animals prey on weaker ones.弱肉强食。
• The lion was hunting for its prey.狮子在寻找猎物。

7 amplified   

放大，扩大( amplify的过去式和过去分词 )； 增强； 详述

参考例句：

• He amplified on his remarks with drawings and figures. 他用图表详细地解释了他的话。
• He amplified the whole course of the incident. 他详述了事件的全过程。

8 thriller   

n.惊险片，恐怖片

参考例句：

• He began by writing a thriller.That book sold a million copies.他是写惊险小说起家的。那本书卖了一百万册。
• I always take a thriller to read on the train.我乘火车时，总带一本惊险小说看。

9 jaws   

n.口部；嘴

参考例句：

• The antelope could not escape the crocodile's gaping jaws. 那只羚羊无法从鱷鱼张开的大口中逃脱。
• The scored jaws of a vise help it bite the work. 台钳上有刻痕的虎钳牙帮助它紧咬住工件。

10 predators   

n.食肉动物( predator的名词复数 )；奴役他人者（尤指在财务或性关系方面）

参考例句：

• birds and their earthbound predators 鸟和地面上捕食它们的动物
• The eyes of predators are highly sensitive to the slightest movement. 捕食性动物的眼睛能感觉到最细小的动静。 来自《简明英汉词典》

11 marine   

adj.海的；海生的；航海的；海事的；n.水兵

参考例句：

• Marine creatures are those which live in the sea. 海洋生物是生存在海里的生物。
• When the war broke out,he volunteered for the Marine Corps.战争爆发时，他自愿参加了海军陆战队。

12 dominant   

adj.支配的，统治的；占优势的；显性的；n.主因，要素，主要的人(或物)；显性基因

参考例句：

• The British were formerly dominant in India.英国人从前统治印度。
• She was a dominant figure in the French film industry.她在法国电影界是个举足轻重的人物。